2-(2-(4-fluorobenzoyl)phenylamino)-3-(4-(2-(9H-carbazol-9-yl)ethoxy)phenyl)propanoic acid is a phenylalanine compound with therapeutic and preventive activity, which has the following chemical structural formula:

The pharmacological activity of the compound is described in Chinese patent application No. CN03126974.5 and U.S. Pat. No. 7,268,157. 2-(2-(4-fluorobenzoyl)phenylamino)-3-(4-(2-(9H-carbazol-9-yl)ethoxy)phenyl)propanoic acid is able to selectively activate PPAR-α, PPAR-γ and PPAR-6, and can be used to treat the diseases associated with metabolic syndrome such as diabetes, hypertension, obesity, insulin resistance, hypertriglyceridemia, hyperglycemia, high cholesterol, arteries atherosclerosis, coronary heart disease, etc.
A preparation method of 2-(2-(4-fluorobenzoyl)phenylamino)-3-(4-(2-(9H-carbazol-9-yl)ethoxy)phenyl)propanoic acid is disclosed in Chinese patent application No. CN03126974.5 and U.S. Pat. No. 7,268,157, and the synthetic route thereof is as follows:

However, the method is accompanied by many side reactions, and the obtained product has many kinds of impurities and high impurity content, which are difficult to be removed by conventional treatment methods (including recrystallization). As a result, purification by chromatography is required, which makes it impossible to perform large-scale industrial production.
Therefore, discovery of the preparation methods of 2-(2-(4-fluorobenzoyl)phenylamino)-3-(4-(2-(9H-carbazol-9-yl)ethoxy)phenyl)propanoic acid suitable for industrial production is still of great importance.